Using a urinary immunoassay to measure aflatoxin metabolites, we examined the associations between exposure to aflatoxin, chronic infection with the hepatitis-B virus (HBV) and background rates of hepatocellular carcinoma (HCC) mortality in a cross-sectional survey of 250 residents from 8 areas of Taiwan with a 4-fold variation in age-adjusted HCC mortality.

Specimens of fasting blood and overnight urines were used to determine HBV carrier status and excretion of aflatoxin in the subjects surveyed.

While the prevalence of hepatitis-B virus carriers showed moderate variability, there was a 500-fold range in urinary aflatoxin levels.

Mean log-transformed levels of aflatoxin metabolites were similar in males and females and in HBV carriers and non-carriers.